Red Brook is home to one of the last self-sustaining runs of sea-run brook trout in southeastern Massachusetts. (Tom Richardson/New England Boating)

By FRANK CARINI/ecoRI News staff

NEW BEDFORD, Mass. — Red Brook is one of the few streams in southeastern Massachusetts that still sustains a healthy brook trout fishery. Actually, that statement is technically incorrect, according to the man who said as much.

Steve Hurley, southeast district manager for the Massachusetts Division of Fisheries & Wildlife, began a recent talk about Red Brook trout at the New Bedford Whaling Museum by correcting himself. Brook trout are actually brook charr, he said, noting that Canadians make this distinction much better than Americans.

Red Brook is a spring-fed, 4.5-mile-long trout, err, charr stream that empties into Buttermilk Bay, not far from the Cape Cod Canal. Much of its length serves as the boundary between Plymouth and Wareham. It has a rich history of use and, some would argue, misuse.

Where the salt water of Buttermilk Bay meets the cold-water springs that feed Red Brook, sea-run — also called salter — trout find the right conditions to lay their eggs, burying them under the stream-bed’s gravel to hide them from predators. But manmade alterations to the stream made trout/charr — a short-lived species of 3-4 years — survival difficult. Red Brook was dammed by dirt structures and concrete dikes to power foundries and mills and to direct water to cranberry bogs.

“Bogs change water levels, add sand and there is a lot of pesticide use associated with them,” Hurley said. “There’s a lot of manipulation that occurs to maintain a bog. You need to build flumes and small dams to control water flow.”

For centuries, starting in the 1700s, the needs of the fish and the ecosystem that supported them were largely ignored. The dams that were built along Red Brook had an enormous negative impact on the fishery, Hurley said. The disappearance of eelgrass to disease in the 1930s also impacted the health of the Red Brook ecosystem, according to Hurley. Buttermilk Bay hasn’t had any eelgrass beds since the mid-1990s.

But a public-private partnership of advocacy groups, state agencies and volunteers completed a restoration project several years ago that has helped return Red Brook to its natural state. For brook trout/charr, the Buzzards Bay watershed is the southern end of their coastal range, according to Hurley, and the work completed about five years ago invited these fish back in greater numbers.

This three-year project included the removal of three concrete flumes — U-shaped dams with cut-out centers that let wooden boards regulate the flow of water. Their removal allowed the current to run freely and scrub natural channels. Between 2006 and 2009, four other dams also were removed.

Restoration work also included the planting of native species to shade the stream and help keep water temperatures cool. Brook trout/charr survive best in water temperatures that range from 34-70 degrees Fahrenheit. Temperatures above 70 degrees, and low flow rates, create a stressful environment, according to Hurley.

This effort, like similar projects completed, ongoing or planned in the area, restored coastal and inland aquatic habitats. Wood, such as tree branches and trunks, were put into the brook to create fish habitat. River herring, both alewife and blueback, American eels and brook trout/charr now swim an unobstructed Red Brook for the first time in 150 years, Hurley said.

One of the first conservationists to address the decline of sea-run brook trout — a variant of the brook trout that grows larger by taking advantage of the ocean’s bounty — in Massachusetts was Theodore Lyman III. In 1867, the state appointed a Fisheries Commission, and one of the commissioners, Lyman, undertook a study of the decline of anadromous fish in coastal streams. He would soon discover that dams and cranberry agriculture were the main causes of the fishery's decline.

By 1870, Lyman began buying land along the banks of Red Brook, Hurley said. His first purchase was a small house, salt marsh and shoreline on Buttermilk Bay. A century later, the Lyman family had acquired 638 acres along Red Brook.

The 210-acre Lyman Reserve, owned by the Trustees, is jointly managed by the three parties. In 2010, the state bought the 245-acre Century Bog from the A.D. Makepeace Co. for $3 million, through a state bond program for land preservation. This acquisition further protected Red Brook, from its headwaters to the sea, and created the 428-acre Red Brook Wildlife Management Unit.

“Protecting the land is key,” Hurley said. “If you don’t protect the land, you can’t protect river habitat. Land protection is key to protecting river fisheries.”